Mars Orbit Insertion and Aerobraking Configuration

The Mars orbit insertion and aerobraking configuration looked very much like the cruise configuration, except that the high-gain antenna was moved to a position that balanced the solar arrays as the spacecraft flew through the upper atmosphere of Mars. The heaviest part of the spacecraft (the propellant tank) also made the spacecraft very stable -- just like a badminton birdie.
Mars Orbit Insertion and Aerobraking

Due to the large area (37.7 square meters or 405.8 square feet) of the spacecraft in this configuration, each pass through the martian atmosphere during aerobraking caused significant slowing, reducing the size of the orbit. Friction from the atmosphere had the additional effect of heating up the spacecraft, so components had to be designed to withstand this heating. The flight team further controlled the heating by changing how deeply the spacecraft dipped into the atmosphere on each orbit.